Categories
Coffee Roasters slow Sustainability/environmental

Good news on coffee bag recycling & re-using air valves

air valve, plastic, environmental coffee packaging
Air valves and metallised plastic are common packaging materials for freshly roasted coffee.

Hopefully we’re all trying to reduce our environmental impact but there are things that we can’t seem to avoid. There is the saying “reduce-reuse-recycle”, but how do we do that with coffee bags? Can we reduce? How would we reuse? And recycling has, until now, seemed impossible.

The problem is that in order to keep freshly roasted (and particularly freshly ground) coffee fresh, it is packed in metallised plastic bags normally with an air valve. Metallised plastic is not recyclable in the general waste stream and so the air valve, even if it is made of a technically recyclable plastic material, is unlikely to be practically recycled.

There are questions as to whether it is necessary to package coffee in this way. A blind taste test by the Nottingham based coffee roaster Roasting House showed that, if your coffee was freshly roasted, a (recycled and recyclable) paper bag was a good option for packaging. Although the flavour profile was different for coffee stored in a bag with an air valve compared with the paper bag after 1 week of storage, the benefit to the taste did not seem to be worth the environmental cost if the coffee is delivered fresh to the customer (within 24 hours or so).

However, perhaps the roaster that you buy coffee from prefers to use the traditional metallised bags with air valves. What can be done there? Fortunately, there has recently been some great news on this front. Has Bean coffee have teamed up with TerraCycle to offer recycling of Has Bean coffee bags. TerraCycle are a company that specialise in recycling (or reusing or up-cycling) hard to recycle materials, such as coffee bags and coffee capsules. TerraCycle takes materials such as coffee bags and either repurposes them (TerraCycle’s website mentions repurposing juice pouches by sewing them together to make rucksacks) or pelletising them to be made into other plastic products.

Earth from space, South America, coffee
Our common home. Can we keep our coffee habit while keeping our home safe for future generations?
The Blue Marble, Credit, NASA: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler

Sadly (but understandably), to take advantage of Has Bean’s offer to recycle your coffee bags you have to be a Has Bean customer. However, all is not lost. If you are not a Has Bean customer you can purchase your own recycling box from TerraCycle for coffee bags (prices start from £73*) or coffee capsules (prices start from £72.36*). Perhaps it is something out of the range of the general consumer but it may be something that smallish coffee roasters with a network of cafés could consider stocking? Do you regularly buy your coffee from a cafe? Why not ask them if they will consider TerraCycle? If you drink coffee from larger companies such as, Tassimo, L’OR and Kenco, there are (free) collection points for their packaging nationwide.

However, what if you don’t buy coffee from either Roasting House or Has Bean nor have easy access to a TerraCycle recycling box? There is one more option in the 3-r’s: re-use. To consider this question, I’ve been experimenting recently with a coffee bag with an air-valve (left over from Roasting House’s experiment that they were happy to send me, thanks Roasting House). Could the air valve be re-used as a valve for fermentation?

Lacto-Fermentation has been in the news a lot recently for the health benefits that it may have. However it is also an interesting and easy way of preserving almost any vegetable. The idea is simple. Mix the vegetables to be preserved in some salt water, store them in a jar and leave them for a few days. That’s it. The salt kills the harmful bacteria while allowing the bacteria that is good for us, the lactobacillus, to thrive. These lactobacillus also produce lactic acid that preserves the vegetables for many weeks while giving them that slightly sour taste of sauerkraut and kimchi.

lacto fermentation, airvalve, air valve, reduce reuse recycle
Can you use coffee bag air valves as one-way lids for fermenting vegetables?

A problem with fermentation seems to be that if you tightly seal the vegetables in a jar, the build up of gas during the fermentation process could mean that the mix explodes. If you open the jar every day to let the gas escape, you may well end up with mouldy cabbage rather than delightfully acidic sauerkraut. This is where the coffee bag air valve comes in. Could you replace the lid with a coffee air-valve and so allow the gas to escape while not having to open the lid every day?

Replacing the glass lid of a Kilner Jar with a lid made from a ring of cardboard (lined with the coffee packaging) and then the coffee bag with air valve seemed to work at first. As had been predicted, my first attempt at fermented spring greens (where I opened the lid each day) had resulted in mouldy cabbage. Successful fermentation came when the glass lid was replaced with the air-valve construction. Could there be a re-use for the air valve?

fermented cabbage
Fermented spring greens. These vegetables have been fermented with salt.

To check whether the valve worked as planned, I used it as a lid for a jar containing bicarbonate of soda and vinegar. As anyone who has played with these substances for making rockets or model volcanoes will know, combining these two substances produces a lot of gas. Again, nothing exploded. However, sadly (?) nothing exploded either when I sealed the air valve with sellotape and repeated the bicarbonate of soda/vinegar experiment. A quick inspection revealed air-gaps between the cardboard ring and the air valve lid and while these could be sealed quite easily, the air valve never seemed to be the primary outlet valve for this set-up.

So, a failure? A null result? Perhaps, but perhaps not. The air valve structure did mean that I was confident that I didn’t have to open the lid on the fermenting cabbage and the cabbage did not turn mouldy before it fermented. Unfortunately, it is hard for me to eat enough fermented cabbage to justify having repeated this experiment enough times yet to be certain! So this is where you come in. Why not have a go at making your own sauerkraut, kimchi or indeed any pickled vegetable (apart from potatoes apparently). Re-use that air valve while reducing food waste. If you do so, please do let me know your design and how it worked (and of course any good fermented vegetable recipes). Alternatively, if you have found another use for those old air valves, or know another coffee roasting company that is recycling its packaging or making efforts to move to  more sustainable packaging, please do let me know in the comment section below, on Twitter or on Facebook.

Enjoy your coffee and your lactobacillus.

*prices correct at time of writing (18th July 2017). Please check TerraCycle’s website for most recent prices. If you are outside the UK, the international website of TerraCycle can be found here.

Categories
Coffee review Science history slow

Coffee & temperance at the Penny, Old Vic

inside the Penny Old Vic
Coffee at the Penny

A café with good coffee in a theatre? I admit to being a little dubious when I first read about Penny at the Old Vic. Fortunately, there was no reason to be concerned. Penny serves Workshop coffee in an unusual setting (even accounting for the fact it is in a theatre). Going through the doors to the Old Vic, you turn left and head down a staircase to the basement where a long counter stretches out in front of you and to your right. Being a theatre café, there were a wide selection of snacks, bar meals, beer and wine in addition to the coffee being served with the La Marzocco espresso machine. As you’d expect, the usual range of coffees were on offer but if you prefer non-dairy milk, there was oat and almond available in addition to the more usual soy based milk. (Although almond milk is one to watch for if you have a tree-nut allergy as there is a risk of cross contamination).

There was also a wide selection of chairs and tables to choose from, ranging from a standard table, to a high table with stools and, around the corner, some chairs that look like you can sink into them and enjoy your coffee way after the performance has been called. The café is open all day (in fact from 8am until 1am on week days) and, if you are not there during a performance is quite spacious (though during the intervals it could probably get quite crowded).

staircase, Old Vic
The lighting on the staircase periodically got brighter and then dimmer. How easy is it to keep our national electrical supply constant such that blackouts and brownouts are not a problem?

The café certainly provides a service for good coffee in Waterloo (it’s within 5 minutes walk from the station) and it is a great place for refreshment if you are visiting the theatre, but is it also the sort of place at which you can slow down and enjoy the moment? The type of neighbourhood café where you can sip your coffee while letting your mind wander onto a café inspired thought train? At first glance, it is perhaps unpromising as it has clearly been renovated and made to be a modern café. But then, thought trains do not happen “at first glance” but as a result of slowing down, sitting, watching and absorbing the surroundings. It is as you do this that I think Penny at the Old Vic starts to speak to you.

The first thing that you may notice is the lighting. A number of different types of lightbulb including an industrial looking art-piece on the stairwell coupled to what appeared to be natural light coming down through another staircase. This theatre was first built in 1816-1818¹ (but with significant rebuilds since then), how was the stage lit at that time? Where did the theatre patrons go to get a cup of coffee or a glass of wine between the scenes and how could they see anything in the dark?

Around 3.5 miles away, one of the first housing developments to have electric lighting was being constructed in the 1860s. The electricity was supplied by seven steam engines housed in a building just off High St Kensington and sent to the new development next door, “Kensington Court”¹. Evidence of the electrical power station (which supplied DC not AC electricity) can still be seen on a stone sign on the building alerting passers by to the “Electric Lighting company”. It is probable that no such set of steam engines provided power for the lighting in the Old Vic, which was more likely still run on candles and gas lighting. However, it is something that was nearly contemporary with the development of Kensington Court that gives this post its title. It is also the reason behind the name of the cafe.

Soya hot chocolate at the Penny, Old Vic
Lord Kelvin got thinking about viscosity as a consequence of drinking a hot chocolate.

In the 1880s, a woman called Emma Cons took control over what is now the Old Vic. When she ran it, the theatre was called the “Royal Victoria Hall and Coffee Tavern” and ran ‘morally decent‘ productions for local people (note though the importance of the coffee to the project!). These productions included scientific lectures for which the entrance fee was a penny, hence, apparently, the Penny café. Apparently she also ran science classes in the disused dressing rooms and, though the mind boggles as to what experiments were done in this theatre at that time, the classes and the lectures were so popular that soon, Cons founded Morley College to continue this adult education. Morley College continues as an adult education college to this day and is now one of London’s oldest adult education colleges.

So it would appear that, even though the Penny café is a relatively new addition to the Old Vic theatre as we know it, the associations between the theatre and coffee (and the theatre and science) go back a long way. First appearances can be deceptive and, with good coffee and much to ponder, the Penny is definitely one to sink into a chair and to listen.

Penny café is in the Old Vic Theatre, The Cut, Waterloo, SE1 8NB

Inside the Penny
Penny at the Old Vic.

¹The London Encyclopaedia, 3rd Edition

Categories
General Home experiments Observations Science history slow

Theme on a V60

bloom on a v60
V60 bubbles. There is much to be gained by slowing down while brewing your coffee.

Preparing a coffee with a pour-over brewer such as a V60 is a fantastic way to slow down and appreciate the moment. Watching anti-bubbles dance across the surface as the coffee drips through, inhaling the aroma, hearing the water hit the grind and bloom; a perfect brewing method for appreciating both the coffee and the connectedness of our world. The other week, while brewing a delightful Mexican coffee from Roasting House¹, I noticed something somewhat odd in the V60. Having placed it on the kitchen scales and, following brewing advice, measured the amount of coffee, I poured the first water for the bloom and then slowly started dripping the coffee through. Nothing unusual so far and plenty of opportunity to inhale the moment. But then, as I poured the water through the grind, I noticed the scales losing mass. As 100g of water had gone through, so the scales decreased to 99g then 98g and so on. It appeared the scales were recording the water’s evaporation.

science in a V60
Bubbles of liquid dancing on the surface of a brewing coffee.

It is of course expected that, as the water evaporates, so the mass of the liquid water left behind is reduced. This was something that interested Edmond Halley (1656-1742). Halley, who regularly drank coffee at various coffee houses in London including the Grecian (now the Devereux pub), noted that it was probable that considerable weights of water evaporated from warm seas during summer. He started to investigate whether this evaporating vapour could cause not only the rains, but also feed the streams, rivers and springs. As he told a meeting of the Royal Society, these were:

“Ingredients of a real and Philosophical Meteorology; and as such, to deserve the consideration of this Honourable Society, I thought it might not be unacceptable, to attempt, by Experiment, to determine the quantity of the Evaporations of Water, as far as they arise from Heat; which, upon Tryal, succeeded as follows…”²

Was it possible that somehow Halley’s demonstration of some three hundred years ago was being replicated on my kitchen scales? Halley had measured a pan of water heated to the “heat of summer” (which is itself thought provoking because it shows just how recent our development of thermometers has been). The pan was placed on one side of a balance while weights were removed on the other side to compensate the mass lost by the evaporating water. Over the course of 2 hours, the society observed 233 grains of water evaporate, which works out to be 15g (15 ml) of water over 2 hours. How did the V60 compare?

Rather than waste coffee, I repeated this with freshly boiled water poured straight into the V60 that was placed on the scales. In keeping with it being 2017 rather than 1690, the scales I used were, not a balance, but an electronic set of kitchen scales from Salter. The first experiment combined Halley’s demonstration with my observation while brewing the Mexican coffee a couple of weeks back. The V60 was placed directly on the scales and 402g of water just off the boil was poured into it. You can see what happened in the graph below. Within 15 seconds, 2 g had evaporated. It took just a minute for the 15g of water that Halley lost over 2 hours (with water at approximately 30 C) to be lost in the V60. After six minutes the rate that the mass was being lost slowed considerably. The total amount lost over 12 minutes had been 70g (70ml).

evaporation V60 in contact with scales
A V60 filled with 400g of water just off the boil seemed to evaporate quite quickly when placed directly on the scales.

Of course, you may be asking, could it be that the scales were dodgy? 70g does seem quite a large amount and perhaps the weight indicated by the scales drifted over the course of 12 minutes. So the experiment could be repeated with room temperature water. Indeed there did appear to be a drift on the scales, but it seemed that the room temperature water got moderately heavier rather than significantly lighter. A problem with the scales perhaps but not one that explains the quantity of water that seems to have evaporated from the V60.

control
Hot water (red triangles) loses more mass than room temperature water (grey squares).

Could the 70g be real? Well, it was worth doing a couple more experiments before forming any definite conclusions. Could it be that the heat from the V60 was affecting the mass measured by the electronic scales? After all, the V60 had been placed directly on the measuring surface, perhaps the electronics were warming up and giving erroneous readings. The graph below shows the experiment repeated several times. In addition to the two previous experiments (V60 with hot water and V60 with room temperature water placed directly on the scales), the experiment was repeated three more times. Firstly the V60 was placed on a heat proof mat and then onto the scales and filled with 400g of water. Then the same thing but rather than on 1 heat proof mat, three were placed between the kitchen scales and the V60. This latter experiment was then repeated exactly to check reproducibility (experiment 4).

You can see that the apparent loss of water when the V60 was separated from direct contact with the scales was much reduced. But that three heat proof mats were needed to ensure that the scales did not warm up during the 12 minutes of measurement. Over 12 minutes, on three heat proof mats, 14g of water was lost in the first experiment and 17g in the repeat. This would seem a more reasonable value for the expected loss of water through evaporation out of the V60 (though to get an accurate value, we would need to account for, and quantify the reproducibility of, the drift on the scales).

V60 Halley
The full set: How much water was really lost through evaporation?

Halley went on to estimate the flow of water into the Mediterranean Sea (which he did by estimating the flow of the Thames and making a few ‘back of the envelope’ assumptions) and so calculate whether the amount of water that he observed evaporating from his pan of water at “heat of summer” was balanced by the water entering the sea from the rivers. He went on to make valuable contributions to our knowledge of the water cycle. Could you do the same thing while waiting for your coffee to brew?

Let me know your results, guesses and thoughts in the comments section below (or on Twitter or Facebook).

¹As this was written during Plastic Free July 2017, I’d just like to take the opportunity to point out that Roasting House use no plastic in their coffee packaging and are offering a 10% discount on coffees ordered during July as part of a Plastic Free July promotion, more details are here.

²E Halley, “An estimate of the quantity of vapour….” Phil. Trans. 16, p366 (1686-1692) (link opens as pdf)

Categories
Coffee review Observations Science history slow Sustainability/environmental Tea

Seeing the light at Cable Co, Kensal Rise

coffee in Kensal Rise, Cable Co
Cable Co, coffee in Kensal Rise

It was fairly late on a February afternoon that we came upon Cable Co on Chamberlayne Road, (opposite Kensal Rise station). With a fairly ‘industrial’ type look, there are plenty of tables at the edge (and in the window) of the café at which to enjoy your coffee. There are also plenty of coffees on offer. Although I had an Americano, I noticed (too late) that pour-overs were available. Coffee is roasted by Climpson and Sons. As it was late in the day, the remaining cakes in the display case all looked to be nutty (or at least likely to be nutty) and so, sadly, I had to wait until I got home for my slice of cake. It was good coffee though, even without the cake, but in a bit of novelty the coffee came ‘deconstructed’, so I got to add the amount of water that I preferred, a nice touch.

Golden light from the setting sun streamed in through the windows (which is a navigation clue & tells you which side of the road this café is on). The effect of the Sun was to bathe the café in light and to silhouette our fellow coffee imbibers making the café take on a film-like atmosphere. The light had another effect though. The steam rising from both the jug of water and my espresso became far more visible than it would normally have been. I watched as the steam clouds formed vortices and turbulent patterns, one fluid (steam) moving through another (air). It was very difficult to catch this in a photograph, a fact that I took in support of my idea that it is impossible to catch the beautiful, beauty is necessarily transient (but my companion in these reviews took as evidence in favour of their idea that I really ought to use a “proper”, manual, camera and not my iPhone).

Steam, scattering, colour
Steam rising from hot water, seen at Cable Co, Kensal Rise

Still, those turbulent rising patterns of steam were visible and that implies that light was being scattered from the droplets of water in the steam. The size of the droplets influences the colour that we perceive when we view the steam clouds. If the clouds appear white, it is because the droplets that are scattering the sunlight have a diameter roughly equal to (or greater than) the wavelength of visible light. The wavelength of light varies between about 400 nm (violet) to 700 nm (red) which means that these water droplets have to be at least 700 nm across. To put this in perspective, the smallest particles of coffee in an espresso grind are about 10 μm diameter which is 14 x bigger than the droplets in the steam cloud.

Of course, how water droplets scatter light above a steaming coffee has implications for our understanding of why the clouds in the sky appear white (and why the sky is blue). Someone who did a lot of early work in understanding the way that light scattered off water droplets in air was John Tyndall (1820-1893). Tyndall was an experimentalist as well as a famous communicator of science. He regularly gave lectures at the Royal Institution that included demonstrations of the experiments that he himself was working on¹. One of these involved scattering light from water droplets (and therefore demonstrating why he thought the sky was blue).

Interior of Cable co
Light streaming into the cafe.

The idea is that sunlight scatters from water droplets differently depending on the diameter of the droplet. When the water droplets are approximately the diameter of the wavelength of red light, 700 nm, there is very little wavelength dependence to the light scattering. Practically this means that the droplets will appear white. If on the other hand, the droplets are much smaller than the wavelength of light, the light scattering starts to be wavelength dependent. So as the droplet gets smaller, blue light (short wavelength) gets scattered a lot by the droplets, while red light (long wavelength) is not scattered so much. This means that if you are looking at a cloud of steam formed by these small droplets at an angle between the sunlight and yourself (say, 90º), the cloud will appear to have a blue tinge. If on the other hand you look straight through the cloud at the sunlight coming in, it will have a red-hue because the blue light will have been scattered out of the cloud leaving only the red colours to come through.

The experiment can be easily demonstrated at home by using very dilute milk in water (see video here or further explanation here). If you put a few drops of milk in a glass of water and then look at the colour of the milky-water as a function of angle, you should see it change from red to blue as you move the glass relative to the light source. The connection with the blue sky seems clear, small particles (in-fact, they can be as small as molecules) scatter blue light preferentially and so, apart from at sunrise and sunset, the sky will appear blue. As Tyndall wrote:

“This experiment is representative, and it illustrates a general principle…. that particles of infinitesimal size, without any colour of their own, and irrespective of the optical properties exhibited by the substances in a massive state, are competent to produce the colour of the sky.”²

Cable Co is at 4 Bridge House, Chamberlayne Road, NW10 3NR

¹A Vision of Modern Science, John Tyndall and the role of the scientist in Victorian culture, U. DeYoung, Palgrage MacMillan, 2011

²Quoted in John Tyndall, Essays on a Natural Philosopher, Ed. WH. Brock, ND. McMillan, RC. Mollan, Royal Dublin Society, 1981

 

http://hyperphysics.phy-astr.gsu.edu/hbase/atmos/blusky.html

 

Categories
Coffee review slow

Pulp fiction in KL?

Freshly roasted coffee, Pulp, Papa Palheta, KL
Coffee on the cutting machine at Pulp

There have been a few great cafés opening up recently in Kuala Lumpur, including Pulp by Papa Palheta in Lucky Gardens. However the space that Pulp occupies is unrivalled: The old cutting room of the Art Printing Works. It really is geek meets hipster in this café, with old electric fittings and the original paper cutting machine housed alongside a fantastic range of freshly roasted coffee.

There is a great range of coffee on offer too. From pour-overs to espresso based drinks and cold brew, Pulp is a great place to discover a wide range of coffees. I had a pour over Ethiopian (Suke Quto) that was beautifully presented with tasting notes ready for me to enjoy. A nice touch was that the cup had been pre-warmed so I got no condensation around the rim of the mug when I filled the cup with coffee. The coffee itself was very fruity, presumably very lightly roasted in order to retain the fruity notes of the beans. (On a second visit I enjoyed a long black which was also very fruity though less so than the pour-over).

pourover at Pulp, Papa Palheta, KL
Taking time with a beautifully presented pour-over

Although there are plenty of seats in this café, on both occasions we visited it was crowded and hard to find a seat. It seems that this is a very popular spot for good coffee in KL, so do be prepared to share a table! Indeed, one of these ‘tables’ is formed from the old cutting machine itself, the machine that used to prepare the paper used for newspapers and books. Sipping coffee here, in a place steeped in the history of printing, it seemed only natural to consider the role in our current society of fake news and whether there is anything that we can do about it.

The issue of fake news or of exaggerated or incomplete news stories is not just limited to issues surrounding the recent US election. Reporting our experimental results honestly and our theories thoroughly underpins all scientific research. However, as funding decisions and employment prospects increasingly depend on publications in prestigious journals, question marks can start to hover over each scientist’s paper (the “publish or perish” problem). Does reporting a result honestly include waiting for that last result (that could contradict or delay the ‘story’ thereby making publication in “high impact” journals such as Nature less probable)? Do we read the papers of others thinking that they have reported everything as truthfully and fully as possible or do we shrug as their next paper (in a lower impact journal) reveals the ‘caveats’ on their previous work? The chemist and scientific philosopher, Michael Polanyi wrote in 1946:

… Suppose scientists were in the habit of regarding most of their fellows as cranks or charlatans. Fruitful discussion between them would become impossible…. The process of publication, of compiling text books, of teaching juniors, of making appointments and establishing new scientific institutions would henceforth depend on the mere chance of who happened to make the decision. It would then become impossible to recognise any statement as a scientific proposition or to describe anyone as a scientist. Science would become practically extinct.“∗

Pulp, Papa Palheta KL
Where else could you see all these old electrical boxes?

Although we are hopefully still very far from that scenario, it is fairly clear that similar levels of trust are required for our society to function well too. For our society to flourish, these same standards of integrity are required of our press (and indeed of ourselves if we publish – or share – articles online). The perception that our society is moving into an era where fake news is as valid as proper investigative journalism has led to some calling ours a “post-truth” era. However, as Emmi Itäranta has argued, we should endeavour to avoid calling our times “post-truth”, in part because the term itself is not neutral. Our words and language matter and when we use the term we contribute to the idea that truth is no longer meaningful.

Such thoughts remind us of our own responsibility and contributions to society. If we don’t want fake news to influence politics, we need to be careful what we share or publish online. From our language to our values, we need to behave as if truth matters. And, to me at least, it seems that enjoying a coffee can help us with that. Stopping to appreciate the moment as we savour our well prepared coffee, we can step-back from the “retweet” or “share” button and think, is this evidence based and true or else, what is it that I gain by sharing this?

It strikes me that cafés such as Pulp, with their mix of great coffee and interesting surroundings are perfect spaces in which to slow down and think rather than react and retweet. Perhaps that is what we need for 2017, more time contemplating in cafés, less time on social media. Let’s hope for some quiet time ahead.

Pulp by Papa Palheta is at 29-01 Jalan Riong, Kuala Lumpur, Malaysia,

∗Michael Polanyi “Science, Faith and Society”, Oxford University Press, 1946

 

Categories
General Home experiments Observations Science history slow Tea

Reflections on physics and coffee

BeanThinking started as a way of slowing down and appreciating connections, often between a coffee and the physics of the wider world but also in terms of what can be noticed in any café. Perhaps, for this first post of 2017, it’s worth spending five minutes looking at your coffee while you drink it to see what you notice. Here are a few coffee connections that occurred to me recently:

reflections, surface tension
Reflections on a coffee.

Parallel lines and surface reflection: The parallel lines on the ceiling of a café were reflected in a long black. Surface tension effects on the coffee meant that the reflections were curved and not at all parallel. A piece of dust on the surface of the coffee was revealed in the reflection by the curved reflections of the ceiling. Astronomers can use similar effects (where images of a star appear in a different location to that expected) to infer the presence of dark objects between distant stars and their telescope. This gravitational lensing can be used to detect quasars or clusters of galaxies.

 

 

 

layering of coffee long black
Layers of coffee

Layering of crema as the coffee is consumed: The coffee stain effect and this layering of the crema suggests a connection between a coffee cup and geology. It used to be my habit to take a mug of tea with me when I taught small groups of undergraduates. In the course of one of these tutorials, a student (who had been observing similar layering in my tea mug) said, “You drink your tea faster when it is cooler than when it is hot”. Full marks for observation, but not sure what it said about his attention during my tutorials! Similar observations though can help geologists estimate the age of different fossils.

 

interference patterns on coffee
Bubbles in coffee

Bubble reflections: An old one but the interference patterns caused by bubbles on the surface of the coffee are full of fascinating physics. The fact that the bubbles are at the side of the cup and seem to be grouped into clusters of bubbles may also be connected with surface tension effects (although there is a piece of weather lore that connects the position of the bubbles to the weather. If anyone ever does any experiments to investigate this particular lore, I’d love to hear about them).

 

 

Coffee, Van Gogh
Art in a coffee cup

Van Gogh’s Starry Night: The effects of vortices and turbulence caused the crema of a black coffee to swirl into patterns reminiscent of this famous painting by Van Gogh. As a result of posting this image on Twitter, @imthursty sent me a link to this preprint of a paper submitted to the arxiv: the connections between Van Gogh’s work and turbulence. A great piece of coffee combining with art and science.

 

So many connections can be made between tea, coffee and science and the wider world, I’d love to see the connections that other people make. So, if you see some interesting physics, science or connections in your coffee cup, why not email me, or contact me via FB or Twitter.

 

Categories
Coffee review General Observations Science history slow

Science & Religion at Rag & Bone Coffee, Westminster

Rag&Bone, Rag & bone, coffee Victoria, coffee Westminster
Rag & Bone Coffee in front of St Matthew’s Church.

Can a coffee cart provide the time and space for reflection and enjoyment of a coffee just as a sit-down cafe can? In seeking an answer to this question (as well as on a quest to find more great coffee in the Victoria/Westminster area), I turned up at Rag & Bone coffee on Great Peter St. It was quiet when I arrived in the courtyard of St Matthew’s Church, and the barista took time to make me a lovely, fruity and full bodied Americano (with beans roasted by Old Spike Roastery). Obviously, there is no seating around the bar but, the church behind the cart is open everyday and offers a rare quiet spot in Victoria to sit and reflect, should you want to do so, before you buy your coffee of course! Sadly, as this is a cart and not a sit-down cafe, the cups provided are disposable, but there is nothing to stop you taking your keep-cup along in order to enjoy your coffee. Just behind the cart, a crucifix above the door of the church caught my eye. And that got me thinking about something, perhaps slightly tangential to the ordinary cafe-physics reviews of Bean Thinking, why do some people imagine there is a conflict between religion and science?

I could see how there could be a disagreement if a religion took an overly literal interpretation of a text (as can happen with disputes over evolution). Or if someone used science as an argument against ‘belief’ while failing to appreciate that science too is based on belief (albeit beliefs that we are most likely just to assume as facts without questioning: particularly that our world exists and that it can be understood). But outside those extremes, and if we look at the motivations of both religion and science, it is surely that both religion and science aim to discover or value truth. If both sincerely follow that aim there can be no real conflict, for truth cannot contradict itself.

Earth from space, South America, coffee
One planet. One home.
The Blue Marble, Credit, NASA: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler

Instead the investigations of one can inform the other and help both to advance our understanding of the world. Take for example the urgent issue of climate change. Scientists, using science as a tool, can investigate and highlight areas of concern for our planet (increasing CO2 levels, rising sea temperatures, a probable increase in extreme weather events, etc) but strictly speaking, as a tool it can go no further. If a scientist then urges us to do something to mitigate climate change, they are not speaking as a ‘scientist’ but as a human being; a human being who is informed by ethical concerns. It would be perfectly logical for someone to recognise that climate change is happening while holding that there is no obligation on our current generation to do anything about it. We may find such an opinion objectionable but that is the crux of it, we have introduced values to the discussion in the form of ‘right and wrong’ and ‘good’. We have moved beyond the remit of science. Religions have had millennia to consider the human condition and what constitutes ‘good’ or ‘right’. For us to combat climate change we need not just the evidence that it is happening, but an idea of a better, or more ‘just’ world. Ethical systems are of course possible without religion, but discussion informed by religious concern can help to change ‘concern for our planet’ into the concern for and protection of ‘our common home‘.

Artemisworks photography, rosary and keyboard
Prayer beads on a keyboard.

Then there is a link between religion and science that brings us right back to Rag & Bone Coffee and St Matthew’s church yard. When St Matthew’s was built back in 1849, the area surrounding it was squalid, conditions were so bad, the area towards Victoria St. was known as the “Devil’s Acre“. The Dean of Westminster, and the new vicar of St Matthew’s recognised that, to help people out of poverty, drastic steps would need to be taken and one of these was to improve education. The Dean of Westminster died soon after St Matthew’s was built but his wife, Mary Buckland, who was also a palaeontologist, wanted to continue his work with the poor. In order to improve the conditions for those living in the slums in the Westminster area, “Mrs Buckland” established a coffee house on Old Pye St, that was cared for by the Revd. Richard Malone, vicar of St Matthew’s. The coffee house was a place where lectures were given and a library was set up. The church and people in the scientific world, worked together to help the poor of the area positively change their living conditions.

The coffee house eventually had to close but, perhaps it could be said that, in a sense, the presence of Rag & Bone coffee in the courtyard of St Matthew’s, continues this work. Although times have changed, and the area is no longer a slum, there is a different form of poverty, people who are time-poor and harassed, working in the offices that now surround the church. In this sense, Rag & Bone Coffee offers not just refreshment, but a brief time-out from the daily grind for the people who now pass by this space. As making coffee is both an art and a science, perhaps we can also say that here too, science and religion work together, with coffee, to make the world a better place.

Rag & Bone Coffee can be found in the courtyard of St Matthew’s Church, Great Peter St. SW1P 2BU.

 

Categories
Coffee review General Observations slow

2 years in

3D hot chocolate art on an iced chocolate, Mace, Mace KL, dogs in a chocolate
Happy birthday to me

Last weekend, Bean Thinking turned 2. So I’ve been looking back at the cafés I’ve visited over the past two years. Bean Thinking started as a way to slow down and to try to see things in a (slightly) different way, to really enjoy the coffee but also to take time to explore the stories, and the science, that can be found in different cafés. I’ve enjoyed the coffee in each café that I have visited but, as always happens, some stick in the memory a little more than others.

So I decided to pull together five cafés which, for me, had an interesting story to tell or prompted an unexpected chain of thoughts. I have sadly had to leave out some great cafés and some really fun stories (for me to think about at least). However, these five stood out. Each café introduced an unexpected bit of science to me, or had something about them that meant that slowing down and enjoying the coffee provided a really special moment. Consequently, each café features for slightly different reasons, and so rather than create a top 5 (which would be impossible anyway), I have listed them alphabetically. I hope you’ll excuse this trip down memory lane.

Amoret, Hammersmith

Kettle drum at Amoret
Coffee on a drum at Amoret

It is not every day that a well made V60 can transport you to another planet. Yet that is what happened for me at Amoret in Hammersmith. The cylindrical design of the table reminded me of a drum but the question is, why do drums make the sounds that they do? The answer to this question took me on a journey into sounds. Just how different would Bach’s famous fugue sound if played on Venus rather than Earth? And then a surreal moment as a Dutch TV station decided to take Bananarama to Venus courtesy of research conducted at Southampton University. This was all accompanied by great coffee in a very pleasant cafe, the review can be found here.

Coffee Affair, Queenstown Road,

Contemplating the floor at Coffee Affair
Contemplating the floor at Coffee Affair

Where better to slow down and appreciate the moment than a place reminiscent of the geology of the South Downs that helped Charles Darwin to argue the case for his theory of evolution. Coffee Affair occupies the old ticket office at Queenstown Road station. The fixings and the floor of the café reveal evidence of the people who inhabited this space in times past. Watching the V60 being prepared, slowly, carefully, exactly, emphasises this sense of time. The result is great coffee in a place that almost forces you to step out of the speed of modern life and stop, put down the smart phone and take time to just notice. Coffee Affair was reviewed here.

Lumberjack, Camberwell,

Lumberjack coffee Camberwell
Exploring local connections at Lumberjack

There’s a strong emphasis on keeping it local at Lumberjack in Camberwell, as well as a preoccupation with all things wooden (this being an enterprise set up with London Reclaimed). So it was interesting to discover that there was a fairly local connection between Camberwell and the ultimate ‘local’ London tree, the London Plane. Not only that, but research that had been published a few weeks before I went to review Lumberjack had shown that, surprisingly, the wind speed needed to fell a tree was fairly constant at around 56 m/s, irrespective of the size or type of tree. This surprising finding was the cherry on the cake for this ultimate in local reviews (here).

Red Door, Greenwich,

vortices, turbulence, coffee cup physics, coffee cup science
Beautiful physics at Red Door

Just what would happen if you put a cup of coffee on a record player? A turntable in a corner at Red Door in Greenwich meant that not only did I start to think about this question, I decided to start some experiments to find out. The resulting physics was physically as well as scientifically beautiful. The experiments can be done by anybody with equipment that you can probably find at home (though I would recommend not using an actual turntable). It turned out to be an elegant experiment involving vortices, but as Helmholtz noticed, similar vortices form in organ pipes, the atmosphere and even in electromagnetism. Truly a beautiful piece of connected physics that I would have missed had I enjoyed my coffee ‘takeaway’. More here.

The Turkish Deli, Borough Market,

Turkish coffee
The universe in a cup of coffee at The Turkish Deli

“The universe is in a glass of wine” so said a Greek poet according to Richard Feynman, but at the Turkish Deli it is more obvious in a cup of coffee. When made properly, Turkish coffee requires at least four minutes of ‘settling time’ before it can be enjoyed. You could use this time to think about how the concentration of coffee particles changes as a function of the depth. Similar considerations led Jean Perrin to conduct experiments back in 1910 that he declared showed that “… it becomes very difficult to deny the objective reality of molecules” (which before that point had indeed been very much denied). Now that The Turkish Deli also roast and grind their own coffee on-site, there is even more reason to visit and ponder the connectedness of our coffee and our planet. The Turkish Deli was reviewed here.

With so many more cafés to explore, and things to discover, who knows what the next year or two will bring. And if you’ve got a recommendation or found a great café where you have stopped and noticed something intriguing, no matter how lateral, why not drop me an e-mail, I’d love to hear your experiences of slowing down and appreciating our coffees.

 

Categories
General Observations slow Sustainability/environmental Tea

Environmentalism through V60s

Is there a parallel between trying to live more sustainably and the art, or science, of coffee appreciation?

San Sebastian via Aeropress
Enjoying a coffee prepared in an Aeropress at Alchemy

Consider the way that we experience our coffees. Who would not wish that more people took time to enjoy great coffees, perhaps single-origin pour-overs, precisely measured and lovingly made, obviously without milk. But we know from experience that not everyone is ready to take the risk of trying a new café and paying that bit extra for a coffee they do not know. Our own coffee journey may illustrate this point. My student days were filled with supermarket (cheapest brand) instant and machine coffee (20p between lectures). Slowly I graduated (quite literally, a well known chain opened close to the university in my final year) to grande lattes, flavoured with nutmeg and similar drinks. A smaller chain introduced me to macchiatos and black coffees before I found a start-up roasting company on the internet and suddenly my mornings were transformed with the fragrance of freshly roasted and freshly ground, aromatic and lovely coffee.

Each step I took introduced me to better, more interesting coffees. New coffee roasters opened offering different levels of roast and different types of bean. Great independent cafés started up which featured coffees brewed in new and innovative ways (the Aeropress was only invented in 2005). Social media and more traditional friend circles introduced me to people who really take time to savour their coffee and which in turn has enabled me to grow in my own coffee appreciation. Would I have jumped from instant to pour-over? Probably not. And yet, I know that I am still on a coffee-appreciation journey: There is still so much more to learn, so many new things to experience, it is a journey I’m very happy to have embarked upon.

kettle, V60, spout, pourover, v60 preparation
How much CO2 does over-filling your kettle really produce?

So what is the link with environmentalism or indeed science? Well, how many times have you heard that if only we filled the kettle just to the correct amount, we would save so many tonnes of carbon dioxide emissions annually? A counter argument points out that given how much pollution we are actually responsible for, merely correctly filling the kettle (or avoiding takeaway cups) is going to have negligible environmental benefit. It is here that I think that the analogy comes in.

It is true that, when you tot up your daily energy consumption, the use of a kettle is not a very big part of it*. For me, even when I overestimated my kettle use (and underestimated the energy costs involved in transporting the kettle/coffee etc. to my kitchen as this became difficult to estimate), my energy use coming from the kettle was only 2% of my daily average. If I only considered the energy consumption due to electricity per day, of course the contribution of the kettle would be higher but it is still not that big a deal.

Over-boiling the kettle does not seem to make that much of a difference when compared to the difference we will have to make in order to limit climate change. Which takes us to the very valid argument that “if everyone does a little, we’ll achieve only a little”†. But, is it worth being just a little bit more optimistic on this? Let’s bring in the coffee.

Earth from space, South America, coffee
One planet. One home.
The Blue Marble, Credit, NASA: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler

It is all too easy to breeze through life not considering our environmental actions, I’d argue that this is the instant coffee stage. As we start to become more aware of the environment, we perform small actions (buying – and of course reusing – a keepcup, only filling the kettle just-so). That’s great, we’re drinking pumpkin-spice lattes. It may not be the best coffee we can get but we are enjoying it. Analogously, as we increase our environmental awareness (and subsequent responsibility) we seem to find that small things become more enjoyable, and even more rewarding. The effort involved in trying to improve our environmental behaviour brings benefits in terms of the amount we enjoy or the appreciation of the things that we have. The small step brought about by considering our kettle use, enables us to make the larger steps that are necessary to behave more environmentally. Trying to make big changes quickly may, in some ways be great (it would indeed be better if everyone appreciated single-origin pour-overs without milk), but it is unlikely to work. To my mind, even if people really started to appreciate good pumpkin-spice lattes that would be a step away from the horrors of instant and towards a better future!

But is an environmental pumpkin spice latte enough? Can I say that I now behave in a properly sustainable and environmental way? Sadly not. Exactly as with the coffee, I am far too aware that I’m on a sustainability journey: There is still so much more to learn, so many new things to experience, it is a journey I’m very happy to have embarked upon. Some do a lot better with the environmentalism, some are still drinking instant coffee, but small steps help us to make the large steps that are going to be needed. Back in the 1990s, as more people began drinking flavoured, grande lattes, so it became possible for the small independent cafes to open up and improve the coffees on offer. We need to move on from pumpkin spice environmentalism, let’s hope we make the steps soon enough.

*You can easily calculate your own energy use with the guidance in David MacKay’s excellent book “Sustainable Energy – without the hot air” that he made fully available online (click the link). In a series of easy steps and estimates that you can make, he helps you to calculate your average daily energy consumption (which can be translated, if you so wished, to a personal carbon dioxide emissions calculation). I would highly recommend going through and looking at your own consumption to see how big an effect, for you personally, over-filling the kettle is.

† Quote from “Sustainable Energy – without the hot air” by David MacKay, UIT Cambridge Ltd, 2009

Categories
Coffee review General Observations slow Sustainability/environmental Tea

Environmentalism inside and out at Farmstand, Covent Garden

Farmstand Drury Lane
Farmstand on Drury Lane

How can we live sustainably, buying locally, being mindful of our ecological footprint and still drink coffee? A recent trip to Farmstand on Drury Lane revealed a café conscious of its environmental responsibilities, somewhere that is trying to help us to make a difference while still enjoying good food and great coffee. Is it possible for us to have our coffee and drink it? The people behind Farmstand certainly seem to think so.

The bare brick walls inside the spacious Farmstand have a certain rustic charm that serves to emphasise the environmental concerns of the café. A focus on local, free range meat and GM free vegetables means that this is definitely a place to be considered when looking for a lunch spot (though on this occasion, we only tried the coffee). Coffee is obviously not locally grown but is roasted by Workshop which is, relatively speaking, just down the road. Tea meanwhile comes from Postcard teas, just up the street. Water is complementary and is provided on tap so as to reduce plastic waste. The service was friendly and with such a bright and airy feel it is a very pleasant space to enjoy an Americano (though I imagine it is fairly crowded at lunchtimes). However, the Americano was served in a take-away cup (when I specified I was staying in). After a bit of digging on their website, I discovered that they use compostable and/or recyclable packaging sourced from London Bio Packaging. However, as it is not easy to either recycle nor to compost cups in regular waste collection (including recycling collections), it would be interesting to know details of how they dispose of their cups so as to know how they reconcile this with the otherwise careful environmental policy.

Interior vertical gardening
Green wall inside Farmstand

As you enter the café, there is a staircase on the left hand side. Potted plants are fixed to the railings making what seems to be almost a miniature green wall. A great way to get houseplants into a small space, this seemed a small scale example of the green walls that are starting to pop up around our cities. Green walls are vertical gardens. They can be grown either with climbing plants or with a second structure on the wall that supports the hundreds of plants. Along with an aesthetic appeal (certainly true of the structure at Farmstand), these green walls have environmental benefits too.

A big environmental problem in cities is particulate pollution from exhausts. Specifically, particulate matter that is less than 10 μm diameter (think Turkish coffee grind) can irritate the lungs and cause health problems for the city’s inhabitants. Particulates less than 2.5 μm diameter are even more dangerous to health. Worldwide, in 2012, 3.7 million early deaths were associated with poor air quality. In London, a 2010 study showed that approximately 4000 deaths per year were the result of exhaust fumes. Which brings us to the first reason that green walls in cities may be such a good thing: Plants adsorb the pollutants.

Green wall Singapore
A green wall at the Ocean Financial Centre in Singapore, Image shared under cc license (attrib. share alike) by smuconlaw.

Over a three month period, a study by Imperial College showed that a single green wall on Edgware Road tube station had removed 515 g of particulate matter from the atmosphere. Using a mix of plants on the wall was found to increase the air turbulence around the wall and so increase the adsorption of the pollutants. Of course, different plants performed differently (in terms of their ability to remove particulate matter from the air). One of the plants on the wall (Convolvulus cneorum) could take out up to 2.73±0.16 g/m² of particulate matter*. On the other hand, another plant on the wall (Hedera helix) took out much less, removing only 0.28±0.02 g/m². However, we know Hedera helix by another name: Ivy. And ivy plants can produce a lot of foliage per plant very quickly. Convolvulus cneorum on the other hand, is a small plant with small leaves. While its efficiency could be very high, the amount of pollution it can remove may not be as great as an ivy plant, purely as a consequence of its leaf size.

Which brings us to questions of aesthetics and practicality. The wall at Edgware Road is planted with many different types of plant in order to produce an effect that reduces pollution while also being good to look at. Similar walls have sprouted up all over the world. However, for short term projects that require a large amount of foliage quickly, planting ivy can be a good option as a pollutant remover. Some of the temporary structures built along Park Lane for the Crossrail project are now covered with ivy. Although I had initially thought that this was due to a lack of weeding, it turns out that this is part of a step towards pollution reduction in our cities (modelling data has indicated that these green walls can reduce the local particulate pollution by 10-20% depending on the geometry of the wall and the plant species growing).

A small step perhaps, but one that is definitely in the right direction. The green wall at Farmstand could therefore be said to illustrate the idea that if we are to make a difference to our external world, we must start by reforming our own interior one. We need to make green walls not green wash and we can start by paying attention to what we plant inside and out.

Farmstand is at 42 Drury Lane, WC2B 5AJ

*The study looked at particulate matter between 2.5 µm and 10µm diameter (i.e. PM(2.5)-PM(10)).